Ciphering apparatus



Allg. 12, 1947; C, R DOTY l 2,425,518

` CIPHERING APPARATUS V Filed Jan. 11, 1944 1o sheets-sheet 1 ATToRNEY Aug' 12, 1947. c; R. DoTY CIPHERING APPARATUS Filed Jan. 11, 1944 l 1o sneeuw-sheet 2 Angl-2,' 1947. Q R DOTY CIPHERING APPARATUS Filed Jan. ll, 1944 4 10 Sheets-Shea?l 3 ATTORNEY Allg. l2, A1947. 1 C, R, DOTY oI'PHERNG APPARATUS Filed Jan. 11,v 1944 10 Sheets-Sheet 4 :gVENTR ATTORNEY Aug. 12, A1947.

c. R. no1-Y CIPHERING APPARATUS Filec; Jan. 11. 1944 1o Sheqts-shget s @im ATTORNEY WG www A N Si Aug. 12,- 1947. Q R DOTY 2,425,518

GIPHERING APPAATUs Filed Jan. L11, 1944 1o shets-sneefv -fw Wm ATTORNEY g. 12, 1947. C', R, DQTY 2,425,518

CPHERING APPARATUS n Filed Jan. 11, 1944 1o sheets-sheet s Aug. 12, 1947. c. R. DorY l y 2,425,518

CIPHERING APPARATUS Filed Jan. 11,'1944 10 sheets-Sheet 9 Aug. 12, 1947. C, R, no1-Y 2,425,5l8-

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' "lDIvEN-ro L ATTRNEY` t' Y Patented Aug. 12, 1947 CIPHERING APPARATUS Charles R. Doty, Yonkers, N. Y., assignor to International Business Machines Corporation, New

York, N. Y., a corporation of New York Application January 11, 1944, Serial No. 517,797

9 Claims. (Cl. 197-4) This invention relates to ciphering and decipher-ing apparatus and its general object is `to provide an improved apparatus for carrying out these operations.

A particular object of the invention is to provde an apparatus of the kind described wherein the permanent parts of the machine constitute a simple arrangement whereby any character can be substituted by any other character, the particular substitution being determined by a control record, such as a, perforated card, or its equivalent. Thus, the machine itself gives no clue to the cipher key employed, the key being embodied in a destructible record, which has the further advantage that the key` can be made indenitely long and the choice of its composition is unlimited. In a preferred embodiment, the control record, in the form of a perforated card, can be set into the machine in various positions, each providing a different cipher key. 'I'here may be, for example, one hundred control cards in a set and these can be exchanged in succession, say, at the end of each line, or any shorter number of character spaces.

Another object is to provide an apparatus of the kind described which facilitates the correction of errors in a ciphered message. With this object in view the apparatus preferably includes a control machine comprising a typewriter having means associated with its carriage for sensing a control record carrying the cipher key, and a controlled machine operated by the control machine to type a ciphered message according to the prescription of the control record. The sensing of the control record follows the movement of the carriage and the control record has different control designation-s for each character space position of the carriage. While a certain control record is in place, there is a particular cipher relation between the control machine and the controlled machine for each character space position of the carriage, and the cipher relation for any character position can be restored by returning the carriage to that character position. Thus, an error can be corrected Iby erasing the erroneous characters on both machines, returning both carriages to the then blank letter space position, and striking the correct key on the control machine.

Still another object is to provide an apparatus of the kind described adapted to be adjusted to plain language condition by the control record.

In .accordance with another feature of the invention, means may be provided whereby the cipher key control by the control record can be modified to the extent of, for example, factorial twenty-six different alphabets.

`Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention'and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is an outline plan view of the entire apparatus.

Fig. 2 is a vertical sectional view through the control machine with parts broken away.

Fig. 3 is a detail view of'the escapement mechanism of the control machine.

Fig. 4 is a vertical sectional view of the control record sensing mechani-sm of the control machine, taken on the line 4-4 of Fig. 1.

Fig. 5 is a vertical section on the line 5-5 of Fig. 4.

Fig; 6 is a small scale front elevational view of the control record sensing mechanism, with parts broken away.

Fig. 7 is a vertical sectional view of the printing mechanism of the controlled machine.

Fig. 8 is a portion of a control card.

Fig. 9 is a diagram showing the relation of the keys of the two machines, for one plugging arrangement.

Fig. 10 is a diagram showing the reciprocal relation of the coding relays to the index point positions of the control record with the codedecode switch in its two different positions.

Figs. 11a.r to 11d are four parts of a complete Circuit diagram of the apparatus.

Fig. 12 is a diagram of the correct arrangement of Fig-s. lla to 11d to form the complete circuit diagram.

Fig. 13 is a table showing a sequence of perforation combinations for a control record and also their eifect on the control relays with the codedecode switch in decode position.

Fig. 14 is a View showing a message to be enciphered.

Fig. 15 is a view showing the same message enciphered.

Before describing the novel features of the invention, the essential parts of the well known machines used in the illustrative embodiment will be briefly reviewed. As shown in Fig. 1, the complete apparatus is composed of three units. At the right is the control machine I, at the left it the controlled machine lill, and between these is a relay box |62 and plugboard ID3. The control machine and the controlled machines are b typewriters and, as shown in the drawing, are similar to the Electromatic typewriter, except for the keyboard. The control machine has, in addition to the standard typewriting mechanism, a control record sensing mechanism |04. It also has key operated switches, to be described presently, connected by the wires of a cable 42 to one row of plugboard sockets 30. The control record sensing mechanism of this machine is also connected by a cable 43 to the relay box |02, The controlled machine has key operating solenoids, to be described presently, connected by the wires of a cable 44 to another row of plug sockets 33.

The control machine As shown in Fig. 2, the typewriter which constitutes the control machine |00 comprises a power driven roller |I0, at the front and back of which are arranged two sets of cams I I I and I I2. The cams are journaled upon oppositely arranged bell cranks I|3 pivoted upon stationary rods ||4. The upper ends of the bell cranks |I3 are connected to their related type bar operating levers I I5 by links I I6. TheV levers I I5 are pivoted upon a stationary rod |I1, upon which key bars |I8 are also pivoted. The key bars control latch levers II9 having latches |20 engaging lugs I2| on the realted cams I|I and |I2, to hold them against the action of spring inuenced arms |22, which tend to rotate the individual cams, to throw their eccentric peripheries toward the roller ||0. The latch levers ||9 are pivoted on the bell cranks I I3 and have upwardly extending arms |23 with bent overV ends |24 engaging in slots of the downwardly extending arms |25 of their related key bars I I8. The type bars, one of which appears at |26 in Fig. 2, are pivotally mounted at |21 upon a basket |28 and are connected at |29 to one part of a toggle mechanism comprising two levers |30 and I3I. The lever |30 is mounted on a fixed pivot |32, while the lower end of lever |3| is connected by a link |33 to the type bar operating lever I I5. A spring |34 holds the mechanism in the normal position shown. Upon actuation of a key bar, the latch lever releases the related cam, which is rocked against the roller ||0 by its spring biased arm |22 and caused to execute one-half revolution, in the course of which it rocks out the bell crank ||3 and operates the type bar. This mechanism is all well known, being fully disclosed in a number of patents, such as Thompson Patent No. 1,873,512.

Behind the type bar basket is a carriage |35 mounted by bal1 bearings |30 upon a stationary guideway |31 and carrying a platen roller |38. The carriage is drawn toward the left (Fig. 1) by a spring of the usual kind (not shown) its movement being controlled by an escapement mechanisrn shown in small scale at |40 in Fig. 2, and on a larger scale in Fig. 3. The escapement mechanism comprises two dogs I4I and |42 loosely pivoted on a stationary pin |43 and urged by springs |44 and |45 into engagement with a rack bar |46 iixed to the bottom of the carriage |35. As shown in Fig. 3, the dog I'4| is slightly longer than the dog |42. The two dogs have tails |41 with which a lever |48 pivoted on a stationary pivot |49 engages alternately to cause the movement of the carriage by successive steps. The lever |48 is connected by a link |50 and spring |5| to a universal frame |52 mounted -by springs |53 and |54 upon stationary posts, one of which is shown at |55, the other being directly behind it. The frame |52 has an arcuate striking bar |56 which is struck by the type bars near the end of their printing movement. The resulting movement of the universal frame |52 rocks the lever |48 and releases one or the other of the two dogs |4| and |42 from the rack bar, allowing the latter, and the carriage to which it is attached, to move one column space to the left (Fig. 1) The escapement mechanism just described is fully disclosed in the patent to Crumrine 1,936,466 and the patent to Thompson et al. 1,994,544.

The bell cranks II3 have downwardly extending arms |51 bearing contact operating rollers |50, to close individual, normally open pairs of contacts |59 each time the related key lever is depressed.

The control record sensing mechanism.-This mechanism comprises a table |60 mounted by two brackets, one of which' appears at I6| in Fig. 2, to the rear side of the main frame |62 of the typewriter. This table is adapted to support a control card Cd (Fig. 8) similar in form to the cards used in International tabulating machines. Above the table |60 is pivoted a strap |63 which is normally urged upward by a spring |64 but which can be turned downward about its pivot |65 and engaged under a snap hook |66. When the strap |63 is elevated, the control card can be slipped under it from the left and inserted beneath two guidebars |61 and |68 spaced slightly above th'e bed upon which the card lies. The card is additionally held by a stationary strap |69 anchored by screws at its right end to the table |60 and raised above the bed enough to allow the card to slip under. The bed |60 has a longitudinal groove |10 in which travel two carriage fingers I1| and |12 secured to the rear side of the carriage |35 and adapted to engage the right and left edges of the control card, when the card is placed upon th'e bed. Thus', as the typewriter carriage moves in either direction, the card is moved by the i'ingers |1| and |12 upon its bed.

The control card- The area of the control card (Fig. 8) is subdivided into vertical columns corresponding, respectively, the character spaces constituting one line of a sheet which is to receive the typewritten record of the message. The vertical columns are subdivided into twelve equally spaced index point positions, individually identified by the column of characters at the left edge of the card. The top and bottom index point positions are both marked X. Between these there is an upper group of five index point positions respectively marked A, B, C, D, E and a lower group of index point positions respectively marked I, 2, 3, 4, 5. Each column contains either an X perforation or a combination of two perforations, one in the upper group and the other in the lower group of index point positions. The functions of the perforations will be explained in detail later.

At the center of the card sensing table is a roller |15 revolubly mounted upon a stationary shaft |16. This roller comprises a cylinder |11 of insulating material, bushings |18 providing bearing contact with the shaft |16, and a metallic outer cylinder |19. Beneath the roller |15 is a row of contact devices, each comprising a contact ball guided in a metallic tube |8I, which is crimped at its upper end to retain the ball against th'e upward urge of a spring |82. The lower ends of the spring and tube bear upon a binding post |83 in the form of a screw having two nuts thereon for the attachment of individual related wires of the cable 43. The metallic parts described are mounted Ain insulating members |84 and |85 secured to the bottom of the table |60 by screws |86. There are thirteen contact devices, twelve being positioned to sense, respectively, the twelve index point positions of the columns of the control card, while the thirteenth is positioned for direct contact with th'e roller |15 beyond the top edge of the control card. The contact devices are individually identified by the reference characters P10, P1|, P12, P13, P14, P15, P16, P11, P18, P19, 1:86a, P8012, P8|. The wires leading off from the binding posts |83 are formed into the cable 43 which runs to the relay box. When the carriage of the typewriter is in its eXtreme right hand position, the control card is located so that the sensing balls sense the rst column, near th'e left end of the control card. The control card has fortyfive columns, the last column at the right being in sensing position when the typewriter carriage is near the left limit of its movement.

The controlled machine-The controlled machine is like the control machine just described, except that there is no control card sensing mechanism attached to it and the keys are provided with electromagnetic operating means. As shown in Fig. '1, the type bar operating mechanism, carriage and escapement are all similar to those described in connection with Fig. 2. In addition, each key has an individual operating solenoid |90, to the armature |9| of which is pivotally connected a lever |92 having a link connection |93 to the related key bar H8.

The coid'z'ng relays and plug/board The box |62 (Fig. 1) contains two groups of gang relays, the rst group being RA, RB, RC,

-RD, RE, and the second group being RI, R2,

`contacts of these live relays are in similar horizontal rows identied by the other small letters of the alphabet, respectively. The a contacts of the relays RI-R5 are in the vertical row a-a and the other contacts of t-hese live relays are in similar vertical rows identied by the other small letters of the alphabet, respectively. Interposed between the contacts of the two groups of relays are twenty-six conductors I, 2, 3, 26. The system, in accordance with which these conductors are connected to the contacts, appears most clearly from the drawings.

In addition to the two groups of relays mentioned, there is a relay RX having twenty-six transfer contacts individually identied by the small letters a, b, c, z. A common wire 46a connects one side of all the a contacts of relays RA, RB, RC, RD, RE to the lower one of the a contacts of relay RX. Wires 46h, 46c, etc., similarly connect the b, c, etc., contacts of the relays RA-RE to the lower one of the b, c, etc., contacts of relay RX. The middle springs of the a, b, c, e contacts of relay RX are connected to respective plug sockets of the row 3|. These plug sockets can be connected in any desired manner by plug wires 32 to individual plug sockets of the row 30. The latter are respectively connected to one side of the pairs of cam operated contacts Ca, Cb Cz (these contacts are identified by reference number |59 in Fig. 2). The other members of these pairs of contacts are connected by a common wire 28 to one side of a battery 21.

The a contacts of the group of relays Rl to R5 15 are connected by a wire 4|c1l to a plug socket of the row 34; the b, c, etc., contacts of said relays are connected by respective wires 4|b, 4|c, etc., to other individual plug sockets of the row 34. 'Ihe latter plug sockets can be connected in any desired manner by plug wires 35 to individual plug sockets of the row 33. The latter plug sockets are respectively connected to the key operating magnets Ma, Mb, Mc Mz of the controlled typewriter (these magnets are identilied by reference number in Fig. 7). The connection of the magnet Me extends through wire 36, a switch 66, and wire 31 to the related plug socket of the row 33. 'Ihe opposite terminais of the magnets Ma, Mb Mz are connected by a common wire 29 to the opposite side of battery 21.

The upper terminals of transfer contacts a, b,

c, e of relay RX are connected by respective wires a, b, c, z directly to wires 4|a, 4|b 4|z. Thus, when the relay RX is energized, the cam contacts Ca, Cb Cz are connected directly to the corresponding magnets Ma, Mb Me.

The control machine and the controlled machine have a number of functional controls, including the case shift, the tabulator, the back space and the carriage return. At the left of Fig. 11a there are shown four pairs of cam contacts, namely, CSh controlled by the case shift key Sh (Fig. 1), C'Ia controlled by the tabulator key TAB, CBS controlled by the back space key BS, and CCR controlled by the carriage return key CR. These contacts are individually connected by wires SH, TA, BS and CR, respectively, to magnets MSh, MTa, MBs and MC1' operating the case shift key lever, the tabulating key lever, the vback space key lever and the carriage return key lever, respectively, of the controlled machine.

Therelay box |02 has a switch 50 which can be moved either to code or decode position (Figs. 1 and llc). This switch operates a plurality of contacts numbered 5|, 52, 53, 54, 55, 56, 51, 58, 59, 60 and 6|. The middle terminals of the switches 5| to 58 are connected, respectively, by wires 19, 1|, 13, 14, 15, 16, 18 and 19, to the binding posts P10, P1|, P13, P14, P15, P16, P18 and P19 of the control card sensing mechanism. In the normal position of the transfer switches 5| to 58, the last mentioned wires are connected, respectively, to wires 90, 9|, 93, 94, 95, 96, 98 and 99 which lead to relays RA, RB, RD, RE, Rl R2, R4 and R5, respectively. The wires 12 and 11 connect binding posts P12 and P11 directly to relays RC and R3, respectively. In the transferred position of switches 5| to 58 the connections of the wires are switches so that wires 10, 1|, 1'3, 14, 15, 16,18 and 19 are connected, respectively, to wires 94, 93, 9|, 99, 99, 98, 96 and 95. The effect of this transfer is to change the relation of the index point positions of the control card to the relays RA-RE and Rl-R5 to establish the reciprocal relation required for decoding.

The relay box |02 also has a switch 65 for changing the apparatus from coding condition to plain text condition, the two positions being indicated in Figs. l and llc by the legends Code and Clean 'I'he operation of this switch will be explained later.

Operation The operation of the apparatus will be described by following through the coding and decoding of the portion of `a message shown in Fig..14. It will be assumed that the control card to be used in this operation will be punched with the combinations tabulated in Fig. 13 in the twenty-two columns occupied by the portion of a message shown in Fig. 14. Below the code combinations there is a tabulation of the decode combinations, which are derived from the code combinations in accordance with the table shown in Fig. 10.

It will be assumed, further, that the plugboard is plugged as shown in the circuit diagram. This establishes a code relation in accordance with the table shown in Fig. 9, that is to say, if the combination of perforations in a column of the control card is A-l, the letter A will code into the letter F, while if the combination of perforations is A-Z the letter A will code into the letter E.

Paper is inserted in the control machine and the controlled machine, the latter being preferably ruled vertically as shown in Fig. 15 to provide a separation into groups of five letters each in the usual manner. The ruling eliminates the need for spaces to separate the groups. The control card is inserted into the sensing mechanism at the back of the control machine in the manner previously described, and the carriages of both machines are moved to their right end positions. The switches 50 and 65 are both turned to code Codina-In the rst column position the combination of perforations shown is B-3. The iollowing circuits are established through these perforations: from the negative terminal of battery 85, through wire 81, contacts 68, wire 8|, contact PBI, roller |15, contact P1I, wire 1|, contacts 52 in normal position, wire 9|, relay RB, wire 33 to the positive terminal of battery 85;' also from. roller |15, through terminal P11y wire 11, relay R3 and wire 88 to the positive terminal of battery 86. The relays RB and R3 are thereby energized.

The T key of the control machine is operated to print the first letter of the message on the check sheet in this machine. The closure of contacts Ct by the cam controlled by the key T of the control machine completes a circuit from. battery 21, through wire 28, said contacts Ct, the corresponding socket 30, plug wire 32 and socket 3|, the t contacts of relay RX in normal position, wire 401i, the t contacts of relay RB, Wire li,A the b contacts of relay R3, wire Mb, the corresponding socket of row 34, plug wire 35, and socket of row 33, magnet Mb, and wire 29, to the other terminal of battery 21. Magnet Mb is energized and operates the B key lever of the controlled machine |0|, causing the latter to print the letter B as shown in Fig. 15. As the type bar of each machine is operated, the carriage is allowed Vto escape to the next column position. In the control machine the control card is also moved one column to the left, breaking the circuits of relays RB and R3 and bringing the sensing balls |80 in index point positions C and into contact with the roller |15. This completes circuits through the relays RC and RI similar to those previously traced.

The next key struck is the O key. This causes an C)v to be printed on the paper in the control machine |00 and the contacts Co to be closed, completing a circuit from wire 28, through said contacts, the related plug connections, the o contacts of relay RX, wire 40o, the ol contacts of relay RC, wire 4, the d contacts of relay RI, wire `an upper case character.

Md, the plug connections, magnet Md and wire 29 to battery 21, energizing said magnet. There by the control machine 10| is caused to print the letter D in column 2. The carriages of both machines escape to column 3.

In column 3 of the message there is a space. The space bar of the control machine |00 is operated and spaces the carriage of that machine to column 4. Before this occurs, relays'RA and R5 having been energized as a result of the perforations in the A and 5 index point positions of column 3 of the control card, the following circuit is completed by closure of contacts CSlp of the control machine: from wire 28, through said contacts, wire 85, contacts 66 and 59, wire 84, the plug connections of rows 30 and 3| pertaining to the letter Z, the z contacts of relay RX, wire 40g, the a, contacts of relay RA, wire 5, the a contacts of relay R5, wire Ma, the related plug connections, and magnet Ma, to the return wire 29, energizing said magnet and causing the letter A to be printed in column 3 by the controlled machine.

The operation continues in a similar manner and it will be assumed that on reaching the letter A in the word channel, the operator erroneously strikes the S key. At this time the control card combination is El; therefore, the relays RE and R| are energized. The closure of contacts Cs completes a circuit from wire 23, through said contacts, the related plug connections, the s contacts of relay RXy wire ds, the s contacts of relai RE, wire i8, the 'r contacts of relay Rl, wire M1', the related plug connections, magnet Mr, to return wire 29. The operator will notice this error in the check copy, perhaps when the line is nnished and proofread before proceeding to the typing of the next line. On noticing the error, the operator erases the erroneous letters S and R on the papers in the two machines and returns the carriage to column l0 position, where the error occurred. This can be done by operating the back space key BS of the control typewriter, which will cause the control machine to back space in the usual manner and will complete an obvious circuit through contacts CBS, wire BS, and magnet MBS, causing the controlled machine |0| to follow the back spacing of the control machine. When the column i0 position is restored, the relays RE and RI are reenergized by the circuits completed by the combination of periorations in column l0 of the control card. When the operator then strikes the A key, a circuit is completed from wire 28, through contacts Ca, the related plug connections, the a contacts of relay RX, wire 1011, the a contacts of relay RE, Wire 26, the z contacts of relayRl wire Me, the related plug connections, wire 31, contacts 60, wire 36, magnet Mz, to return wire 29, energizing said magnet and causing the letter Z to be typed by the controlled machine. In column |1, the character to be typed is a hyphen,

In this column position the relays RD and Ril are energized. The operator rst depresses the case shift key Sh, causing the type basket of the control machine to drop to upper case position. This closes the contacts CSh, completing a circuit from wire 20, through said contacts, wire Sh, and magnet MSh to return wire 25, energizing said magnet and causing the controlled machine to shift to upper case position. The operator then strikes the hyphen key (the A key), a hyphen is printed in column I1 of the control machine, and contacts Ca are closed to complete a circuit from wire 28,

Decodinlg In decoding the ciphered message shown in Fig. 15, the machines are prepared in the same way as for coding, except that the switch 56 is shifted to decoding position. A control card identical to the one used in coding, is set up on the card sensing table |60 of the control machine, With the carriage of this machine in its right end position, the contact balls |86 sense the perforations of column l. This time, however, due to the change in the position of switch 50 the relay RD is energized instead of relay RB (see the code-decode table, Fig. 10), The circuit extends through contact device BTI, wire 1|, switch 52 in transferred position, wire 93, and relay RD to return wire 88. The relay R3 is energized through a circuit extending from contact device P11 through Wire 11, the same as for coding. When the operator strikes the B key of the control machine, a circuit is extended from wire 28, through contacts Cb, the related plug connections, the `b contacts of relay RX in normal position, wire 46h, the b contacts of relay RB, wire 22, the t contacts of relay R3, wire dit, the related plug connections, magnet Mt, and return wire 29 to battery 21, energizing said magnet. The T type |bar of the controlled machine is operated to print the first letter of the message being decoded.

In the third column the relays RE and Rl are energized. When the A key is depressed, the circuit is extended from wire 28, contacts Ca, the related plug connections, the a contacts of relay RX in normal position, wire 40a, the a contacts of relay RE, wire 26, the z contacts of -relay RI, wire 41a, the related plug connections, wire 31, switch 6I, wire 38, magnet MSp and return wire 29 to battery 21, energizing said magnet and operating the space bar of the controlled machine.

The other circuits utilized in the decoding operation can be traced out in the same way. It will be observed that the letter Z is ciphered into the same letter as a space, while the letter into which Z is ciphered will decipher into a space.

If it is desired to print any part of the message in clear text, the control card can -be perforated in one f the two X index point positions for every column in which clear text is to be printed. This will cause a circuit to be completed, in those columns, through contact device P8811 or P861), wire 80a, or 8022, wire 86, switch 61 in normal position, wire 69, relay RX and return wire 88 to battery 86. With the contacts of relay RX in transferred position, the closure of any one of contacts Ca, Cb Ce extends a circuit through the related plug connections, the related contacts a, b, c, z of relay RX, the related wire a, b, e, and through theplug connections to the solenoid Ma, Mb Mz of the controlled machine, corresponding to the key of the control machine which was operated.

If it is desired to operate the machines continuously in clear text, the switch 65 is shifted to the clear position. This opens switch 68, so that none of the relays RA-RE and RI-R can be energized. The contacts 61 transfer, connecting battery 86, through wire 81, said contacts in transferred position, wire 89, relay RX and return wire 88 to battery 86, energizing said relay and establishing the clear text relation of the two machines. The contacts 66 transfer so that, when the space bar is operated, a circuit is extended from wire 28, through contacts CS1), said contacts 66 in transferred position, wire 38, magnet MSp and return wire 29 to battery 21.

The control cards can be utilized in various Ways, to vary the cipher key derived from a single set of cards. For example, instead of leaving one card in for a full line, the cards may be exchanged after printing half a line, or any smaller fraction -of a line. Each card can be turned in the plane of thecard through so that the bottom edge becomes the top edge. In this position the upper and lower` groups of index point positions are reversed and their control laccordingly modified. Furthermore, the card can be turned in another direction to place it face down upon the card table so that the sequence of perforation combinations is run through in reverse order. In the face down position, the :card can also be turned through 180 in the plane of the card, to bring the bottom edge to the top. Thus, each card provides four different ciphering sequences.

The control by a single control card can be modified by means of the plug connections, in accordance with factorial twenty-six different a1- phabets. If the plugging shown in the 'drawing is changed, the table shown in Fig. 9 will be changed accordingly. In changing the plugging it is yonly necessary to insure that the connections of sockets 30 to sockets 3l agrees with the connection of sockets 33 to sockets 34. To facilitate the plugging operation and to prevent errors, the wires 32 and 35 can be sheathed in pairs, with two-pronged plugs at each end. Thus, when the prongs of one plug are plugged into a pair of vertically aligned sockets in the rows 3l] and 33, the wires connected to said prongs can only be connected to a pair of vertically aligned sockets in the rows 3l and 34, by the two prongs of the lplug at the other end of the two wire cable. To insure against connection of a socket in row 36 to a socket in row 34, the two prongs of each plug can be suitably differentiated by size or shape, in well known manner.

Since the apparatus with the exception of the control cards is merely a means whereby any different cipher relation can be established between the control machine and the controlled machine, the machines themselves give no clue to the cipher key. The latter is determined by the punching of the destructible cards and by the plug connections which can be removed at any time without trace.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a single modification, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made 4by those skilled in the art without departing from the spirit of the invention. For example, while I have shown in the drawing a controlled typewriter wherein the keys are operated by individual solenoids, any equivalent means for selectively operating the character manifesting devices of the controlled machine may be substituted. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In a ciphering apparatus, a set of key op- 1-1 erated switches,v a set of charactei manifesting devices, a set ofelectricallyoperable devices, one for each keyV operated switch, for causing the selective operation of said character manifesting devices, two groups of gang relays, the'relays of o-ne group each having contacts connected,y respectively, to said electrically Ioperable devices, while the relays of the other group each have contacts connected, respectively, to said key operated switches, Veachv of `said -contacts having a complementary contact and saidcomplementary contacts of the two groups of relays being interconnected in combinational arrangement, whereby each key switch can be connected to any one of said electrically operable devices by-selective operation of said relays in various-pairs, each pair comprising a-'relayof each group, each one of said key switchesbei-ng connected to a different one of said electrically operable devices by each paired operation of saidrelays, andl means controlling the operation of said relays comprising a control member having variouslypositioned control designations thereon, sensing means for said designations comprisingv a plurality of sensing elements, respectively connected to diierent i ones of said relays, and means for relatively shifting said control member and said sensing means.

2. A cipheringapparatus as described in claim 1, wherein the control designations are located in various positions within two different elds of the control member, the individual sensing elements of said sensing means being adapted to sense related designation positions of the two fields, the sensing elements pertaining to o-ne field being operatively associated, respectively, with the relays of one group and the sensing elements pertaining to the other eld'being operatively associated, respectively, with the relays of the other group.

3. A ciphering apparatus as described in claim l, wherein the control designations are located in various positions within two diierent fields of the control member, the individual sensing elements of said sensing means being adapted to sense related designation positions of the two elds, the sensing elements pertaining to oneeld being operatively associated, respectively, with the relays of one group and the/sensing'elements pertainingto the other-field being operatively associated, respectively, with the-relays of the other group, the iields being symmetrically arranged on the control member, so that the latter can be turned to reverse the relation of the eldsto the sensing elements. v A

4. A ciphering apparatus as described in claim l, wherein code-decode switch means are provided and adapted to modify theV control of said sensing means over said relays, so that the same control designations of the control member will cause av diierent interconnection between said key switches and said electrically operable de'- vices when said switch means is in decode position than when it is in code position, the interconnection in the decode position being the reciprocal of the interconnection in the code position.

5. A ciphering apparatus of the type wherein a plain text and a cipher text are printed simultaneously by two printing mechanisms, under control of a single keyboard, the plain text being printed one characterafter another on a record sheet supported by a carriagev which moves-stepby-step as the-characters Yare printed, characterized by cipher control meansmo-vable progressively with the carriage to change the cipher relation between the keyboard and the cipher text printing mechanism as the printing progresses, said cipher control means being movable reversely, with the carriage to any previous position, to restore thecipher' relation which existed 'at said previous position.'

6.' Acipher apparatus'as described in claim 5, wherein saidfcipher controlfmeans comprises a control member having 'variously positioned' control designations thereon, Ia'holding device to position said control member, and a sensing' de- Vice to A'senseV the designations of said control member, said devices being 'relatively' movable in either direction to"'establi'sh effective sensing relation between saidl sensing device and particular designations of said control member.

7. A cipher apparatus as described in claim l., wherein transfer means are provided to disconnect said key switches from their related contacts of said relays and to connect said key switches directly to their corresponding electrically operated devices, said sensing means having a sensing element to sensea control designation in a special position of the card, said last element being operatively connected to said transfer means so as to transfer the same on sensing of a designation in said special position.

S. In a cipher apparatus of the kind comprising a typewriter having a keyboard, type members 'controlled' thereby, a carriage to support a record sheet, and escapernent means for the carriage operated under control of the keys, combined with a second typewriter comprising type members controlled by the same keyboard through variable cipher means adapted to change the individual relations of the keys of said keyboard to the type membersV of said second typewriter; control means for said cipher means comprising a perforated` card, stationary sensing means therefor, andY holding means for said card connectedto said carriage rso as to move said card pastsaid sensing means as Said'carri'age moves, said` cipher 'means having setting means connected to said sensing means and responsive to the sensing of perforations in different positions on saidcard to vary saidcipher means.

9. A cipher'ing apparatus Aas described in claim 1, wherein plugging means` are included in the connections between the vcontacts of the relays -of one group and said electrically operable devices,

and in the connections between the contacts of the relays of the other'group and said key operatedswitches'for Varying the effect of said` relay'controlling means.

` CHARLES. R.DTY.

REFERENCES CITED` The followingk references are Vofrecord in the le of this patent.;

UNITED-:STATES PATENTS 2,055,702 Patton Seli. 29, 1935 

